JPH02140243A - Glittering plastic - Google Patents

Abstract

PURPOSE:To obtain glittering powder having improved heat-resistance to suffi ciently endure the processing temperature without deteriorating the transparency of plastics by compounding a specific primary-coloring metallic pigment. CONSTITUTION:A primary-coloring metallic pigment is produced by chemically adsorbing a coloring pigment to the surface of a metallic pigment via a carboxylic acid having one double bond and two carboxyl groups and produced by the thermal polymerization of one or more kinds of carboxylic acids having double bond. The primary-coloring metallic pigment is compounded in an amount of 0.1-50 pts.wt. (in terms of non-volatile component) to 100 pts.wt. of a plastic. If necessary, the composition is further added with other colorants and additives. The primary-coloring metallic pigment is further coated with a polymer com posed of a radically polymerizable unsaturated carboxylic acid and a monomer having >=3 radically polymerizable double bonds. The secondary-coloring metallic pigment produced by the above process is compounded in an amount of 0.1-60 pts.wt. (in terms of non-volatile component) to 100 pts.wt. of plastic.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a glittering plastic that has a metallic color appearance by containing a colored metallic pigment as a glittering pigment.

[Conventional technology]

Conventionally, in order to give metallic luster to plastic sheets and molded products, gold and silver colors were created by applying mechanically crushed metal powder such as brass powder or aluminum powder in the form of paint or ink to the plastic surface. Also, the metal powder mixed with the metal powder and molded is usually used, and by mixing coloring pigments and dyes with the metal powder, various colors with glittering properties can be expressed. ing.

[Problem to be solved by the invention]

However, although the method of applying paint or ink is easy, it is expensive and is not suitable for mass production.

In addition, when metal powder is mixed into plastic materials, coloring pigments and dyes must be mixed and used in order to express glittering colors other than those that can be expressed with brass powder or aluminum powder. As the amount of pigments and dyes used increases, the transparency of the plastic disappears, the luster disappears, and the color becomes darker.

In order to overcome these drawbacks, attempts have been made to mold plastic materials by mixing crushed powder obtained by lining both sides of an aluminum vapor-deposited layer with colorless or colored resin layers. However, when this crushed powder is used in injection molded products of thermoplastic resins such as PE, PP, and PS, which are usually used in large quantities, there are problems with heat resistance and the brightness, which is the most important feature, is greatly reduced. , may be lost in some cases.

[Means to solve the problem]

As a result of intensive research, the present inventors aimed to develop a glittering powder that has sufficient heat resistance and can withstand the processing temperatures of the resin used without impairing the transparency of the plastic. As a pigment for glittering plastics, a carboxylic acid having at least one double bond and two carboxyl groups (hereinafter referred to as thermally polymerized carboxylic acid) is obtained by thermally polymerizing one or more carboxylic acids having a double bond on the surface of a metallic pigment. By using a primary colored metallic pigment made by chemically adsorbing a colored pigment, or a secondary colored metallic pigment made by coating this pigment with a resin, the drawbacks of the conventional pigments mentioned above can be overcome. It was found that this problem could be overcome, and the development objective was achieved and the present invention was completed. In other words, by coloring each opaque metallic pigment with high specular reflectance, each secondary or secondary colored metallic pigment becomes the size of the metallic pigment base, and the pigments of each color are mixed. The result is a pigment that has the major characteristic that its brightness remains the same even when the color changes. On the other hand, with ordinary colored pigments made of ultrafine powder, the larger the amount used or the more types of pigments (i.e., types of colors) mixed, the darker the color becomes, approaching black as much as possible.

Therefore, by appropriately combining the primary or secondary colored metallic pigments of the present invention and kneading them into plastic, it is possible to express various glittering colors.

The configuration of the present invention will be explained in detail below in order.

(Regarding pigments) The primary colored metallic pigment used in the present invention is a carboxylic acid having at least one double bond and two carboxyl groups obtained by thermally polymerizing one or more carboxylic acids having a double bond, and a metallic pigment. Stir the pigment in an organic solvent,
It is produced by mixing the filtered cake and the colored pigment with cross-mixing or stirring in the presence of an organic solvent, and then removing the excess organic solvent.

In addition, secondary colored metallic pigments are produced by stirring a thermally polymerized carboxylic acid and a metallic pigment in an organic solvent, then mixing the filtered cake and the colored pigment with crosstalk or stirring in the presence of an organic solvent, and then mixing the filtered cake and the colored pigment with stirring in the presence of an organic solvent. After adding a radically polymerizable unsaturated carboxylic acid while dispersing and stirring in a solvent, a monomer having three or more radically polymerizable double bonds and a polymerization initiator are added and polymerized, and excess organic solvent is removed from this. It is made by

(- Regarding secondary colored metallic pigments) - Coloring pigments used for secondary colored metallic pigments etc. may be either organic pigments or inorganic pigments as long as they do not dissolve in the organic solvent used, but thermally polymerized carboxylic acid adsorption It is necessary that the colored pigment is stably adsorbed to the treated metallic pigment.

Specific examples of organic pigments include azo lake pigments, insoluble azo pigments, condensed azo pigments, phthalocyanine pigments, threne pigments, indigo pigments, perinone pigments, perylene pigments, phthalone pigments, dioxazine pigments, and quinacridones. pigments, isoindolinone pigments, metal complex pigments, etc.

Examples of inorganic pigments include yellow lead, yellow iron oxide, red iron oxide, cobalt blue, carbon black, and titanium oxide.

Examples of organic solvents include aliphatic hydrocarbons such as hexane, heptane, octane, and mineral spirits; aromatic hydrocarbons such as benzene, toluene, solvent naphtha, and xylene; esters such as ethyl acetate and butyl acetate; tetrahydrofuran and diethyl ether. Examples include ethers such as These organic solvents are usually used alone or in combination, but when producing a secondary colored metallic pigment, it is desirable to use the same organic solvent as used in producing the secondary colored metallic pigment.

Further, as the thermally polymerized carboxylic acid, for example, a thermally polymerized carboxylic acid obtained by thermally polymerizing linseed oil fatty acid or soybean oil fatty acid is used.

The amount of thermally polymerized carboxylic acid to be used varies depending on the surface area of the metallic pigment used and the amount of colored pigment used when producing the secondary colored metallic pigment, but is based on 1.00 parts by weight of 1 d/gr metallic pigment. It is preferably 0.2 to 10 parts by weight, particularly 1 to 3 parts by weight.

In order to produce a primary colored metallic pigment using the above raw materials, first, the metallic pigment and the thermally polymerized carboxylic acid are added to an organic solvent, the temperature is raised, and the mixture is thoroughly stirred. The amount of organic solvent does not need to be strictly determined as long as vigorous stirring is possible and the thermally polymerized carboxylic acid is evenly adsorbed on the surface of the metallic pigment.
Approximately 1 to 3 parts by weight of the metallic pigment is used per 100 parts by weight of the organic solvent. The temperature should preferably be below 60°C, 60°
Above C, the chemical adsorption rate becomes too fast and it becomes difficult to adsorb uniformly. The time tends to be shorter as the temperature is higher, and is selected appropriately.

After the above operation, it is filtered using a filter press or the like, and the metallic pigment having a layer of thermally polymerized carboxylic acid formed on its outer surface is recovered as a filter cake.

Next, the recovered thermally polymerized carboxylic acid-treated metallic pigment is placed in a container, and a colored pigment that has been dispersed and stirred with an organic solvent is added to this container using a pot mill (small ball mill) containing chrome steel balls, etc., and cross-mixed or stirred. Mix.

The optimal conditions for dispersing and stirring colored pigments differ for each pigment, but
The organic solvent may be used in an amount of 1 to 5 parts by weight per 1 part by weight of the colored pigment. Further, when 0.02 parts by weight of a pigment dispersant is added, the dispersion becomes even better.

At this time, if the amount of the organic solvent is too large, the chemical adsorption of the colored pigment to the thermally polymerized carboxylic acid-treated metallic pigment will be poor, and if the amount is too small, mixing and stirring will become difficult.

The organic solvent that is contained in the thermally polymerized carboxylic acid-treated metallic pigment paste and the one used for dispersing and stirring the colored pigment are inevitably used, but including the total amount of these, the metal content of the metallic pigment 10 per 100 parts by weight
~200 parts by weight is preferred.

In addition, the amount of coloring pigment varies depending on the surface area of the metallic pigment (actually, there is an inverse correlation with the particle size, so the particle size is used instead), but the average particle size is 22IEnSWCA (water-covered surface area of aluminum powder) of 7400c♂/gr aluminum pigment. In this case, it is preferably 1 to 50 parts by weight, particularly 5 to 20 parts by weight, based on 100 parts by weight of the metal content.

If the amount of color pigment is less than 1 part by weight, the color appearance will deteriorate, and if it exceeds 50 parts by weight, the adsorbed amount will be too large and not only will the metallic feel be impaired, but unadsorbed color pigment will remain, which is uneconomical.

If the average particle size is coarser than the above, the surface area will be small and the amount of color pigment used must be reduced accordingly; if the average particle size is finer than the above, the surface area will be very large. Color pigments must also be used in correspondingly large amounts.

The above operation is performed at 60° C. or lower, and the time is appropriately selected depending on the respective temperature. When the temperature exceeds 60℃,
The adsorption speed becomes too fast, making it difficult to be evenly adsorbed.

Instead of adsorbing the colored pigment by stirring in the container, the colored pigment may be dispersed and mixed using the pot mill, and a thermally polymerized carboxylic acid-treated metallic pigment may be added thereto. At this time, the amount of organic solvent used can be minimized.

When using the primary colored metallic pigment obtained by the above method as a pigment, the organic solvent is separated and used, and when used as a raw material for a secondary colored metallic pigment,
It is used while retaining the organic solvent.

In either of these cases, the unadsorbed colored pigment may be removed by decantation or the like using an organic solvent.

The above-mentioned sub-colored metallic pigment is one in which the coloring pigment is chemically adsorbed onto the surface of the metallic pigment via thermally polymerized carboxylic acid, and is not physically fixed by coating with resin, etc. When intense force is applied, such as during processing, or when a considerable amount of thermally polymerized carboxylic acid or a substance equivalent to it is present in the system, the chemically adsorbed color pigments described above may be desorbed. Otherwise, the features of the present invention will be lost.

However, if the above-mentioned intense force is not applied, and if a desorption agent is not included, there is no coating resin, so it is compatible with the resin used, and there is no interface between different resins, so the light reflectance decreases. It exhibits a superior metallic color feel than secondary colored metallic pigments.

(Regarding secondary colored metallic pigments) - Secondary colored metallic pigments cannot be vigorously stirred, but by further processing them, secondary colored metallic pigments that are water resistant, chemical resistant, and have an excellent metallic color feel can be produced. A colored metallic pigment is obtained.

Examples of radically polymerizable unsaturated carboxylic acids used to produce secondary colored metallic pigments include acrylic acid, methacrylic acid, itaconic acid, and fumaric acid. used.

In addition, examples of heptamers having three or more radically polymerizable double bonds include trimethylolpropane triacrylate, trimethylolpropane trimethacrylate,
Examples include tetramethylolmethane triacrylate and tetramethylolmethanetetraacrylate.

In addition, the polymerization initiator may be one that is generally known as a radical generator, such as peroxides such as benzoyl peroxide, lauroyl peroxide, isobutyl peroxide, methyl ethyl ketone, and azobisisobutyronitrile. etc. can be mentioned.

To make secondary colored metallic pigments using these,
Add the above organic solvent and primary colored metallic pigment to a sufficiently stirrable amount of organic solvent, add the radically polymerizable unsaturated carboxylic acid while stirring vigorously, and then add 3 or more radically polymerizable double bonds. A monomer and a polymerization initiator are added and polymerized. If the amount of the above-mentioned organic solvent is too small, the viscosity of the reaction system will become too high once polymerization starts, making it difficult to coat each colored metallic particle with resin, and multiple particles will overlap and become coated with resin. , which causes poor dispersion when added to plastics. If the amount of the organic solvent is too large, production efficiency will deteriorate. Through the above polymerization operation, the primary colored metallic pigment is covered with a highly crosslinked three-dimensional resin layer, forming a secondary colored metallic pigment with excellent stable water resistance and chemical resistance, and excess organic solvent is filtered out. By separating by drying or the like, a secondary colored metallic pigment can be obtained.

In the above reaction, it is preferable to replace the reaction system with an inert gas such as nitrogen or argon. In addition, the time from adding the radically polymerizable unsaturated carboxylic acid to adding the monomer having three or more radically polymerizable double bonds and the polymerization initiator is the same as that of a three-dimensional polymer with good adhesion. It is preferable to leave an interval of at least 5 minutes or more in order to obtain . The temperature of the polymerization reaction varies depending on the type of polymerization initiator, but is between 30 and 150°C, and the reaction time is appropriately selected depending on the temperature, but is in the range of 30 minutes to 10 hours.

If the above polymerization reaction is carried out using only a monomer having three or more radically polymerizable double bonds and a polymerization initiator without using a radically polymerizable unsaturated carboxylic acid, the polymerization system will not only become viscous and unable to be stirred, but also become unstable. A strong film cannot be obtained.

This shows that it is essential to cover the surface of the secondary colored metallic pigment with a radically polymerizable unsaturated carboxylic acid in advance.

(Regarding plastics) The plastics used in the present invention include cellulose plastics, high-density polyethylene, low-density polyethylene, polypropylene, polyamide, polycarbonate, polyacetal, polyphenylene sulfide, vinylidene chloride resin, polyethylene] 3 Crystalline thermoplastics such as lenterephthalate Resin, vinyl chloride resin, polyvinyl alcohol, polyvinyl butyral, polystyrene, ABS resin, methacrylic resin, polyphenylene oxide, polyurethane, non-grade thermoplastic resin such as ionomer resin, phenolic resin, urea resin,
Examples include thermosetting resins such as melamine resins, unsaturated polyester resins, diallyl phthalate resins, epoxy resins, silicone resins, alkyd resins, and polyimides.

(Other Additives) As other additives, plasticizers, ultraviolet absorbers, anti-aging agents, lubricants, and if necessary, other colorants may be used in combination.

(Molding method) The method for molding the glittering plastic of the present invention is to mold a glittering colored pigment blended into a base resin using a casting molding method, an injection molding method, an extrusion molding method, a blow molding method, a transfer molding method, Molded by thin plate molding method, cold press molding method, etc.

When producing the glittering plastic of the present invention, if a so-called masterbatch is prepared by containing a colored metallic pigment as a glittering pigment in a base resin at a high concentration and pelletizing it, it is possible to make an actual molded product. It makes the work easier and allows for uniform mixing.

[For production]

According to the present invention, since each pigment particle has glitter, a plastic with excellent glitter in all color tones can be obtained.

The present invention will be explained below with reference to Examples.

Example 1 400 ml of mineral spirit was placed in a 100'Oml Mitsuro flask, and 168 g of aluminum pigment (flake aluminum paste, metal content 71.5%, average particle size 70 um), acrylic acid and soybean oil fatty acid were heated. 2.4 g of polymerized thermally polymerized carboxylic acid (manufactured by Harima Kasei Kogyo Co., Ltd., Diazid) was added, the temperature was maintained at 55°C while introducing N2 gas, and the mixture was vigorously stirred for 1 hour, then cooled to room temperature. was filtered to obtain a thermally polymerized carboxylic acid-treated aluminum pigment. The amount of diazid adsorbed on this aluminum was 2.2 g.

In addition, 1.50 ml of xylene and a yellow pigment (manufactured by Ciba Geigy, Cjnquasia P
a5tGold YT-915-D) 14g and pigment dispersant (manufactured by Kao Corporation, homogenol L-100)
0.28g was added and rotated at 30rpi+ for 16 hours to disperse and pulverize the yellow pigment.

Next, the aluminum pigment adsorbing Diazid and the dispersed and pulverized colored pigment were placed in a 500 ml Nillo flask together with 80 ml of mineral spirit.
The colored pigment was adsorbed onto the surface of Diazid by vigorous stirring for 10 minutes at room temperature while introducing N2 to obtain a primary golden aluminum pigment.

A body of a radio cassette recorder was prototyped using an injection molding machine at 220 DEG C. from a mixture of parts by weight of this golden yellow aluminum pigment IO and 100 parts by weight of polystyrene chips.

The obtained body had a -sub-golden aluminum pigment sufficiently dispersed therein, and exhibited a beautiful golden luster.

Example 2 150 g of the primary golden aluminum pigment prepared in Example 1, Net, was placed in a Mitsuro flask containing 1600 ml of mineral spirit without removing the mineral spirit, and 2.4 g of acrylic acid was added.
Stirred for 15 minutes at a temperature of 0°C. Next, 30 g of trimethylolpropane trimethacrylate and 3.4 g of azobisisobutyronitrile dissolved in 170 ml of mineral spirit and 150 ml of mineral spirit were added, and the temperature was raised to 100°C for 3 hours to polymerize, resulting in a golden yellow color. The surface of the aluminum pigment was coated with a resin. Excess mineral spirit was removed by filtration to create a secondary golden aluminum pigment.

A body obtained by injection molding a mixture of 15 parts by weight of the secondary golden aluminum pigment and 100 parts by weight of polystyrene chips in the same manner as in Example 1 has the secondary golden aluminum pigment sufficiently dispersed and As in Example 1, it exhibited a beautiful golden luster.

Example 3 A mixture of 20 parts by weight of the secondary golden aluminum pigment of Example 2 and 100 parts by weight of low-density polyethylene (LDPE) chips was melted, poured onto a glass plate coated with a mold release agent, and cooled. A plank with a golden luster was obtained.

Example 4 6 ml of xylene and blue pigment (manufactured by Dainippon Ink and Chemicals Co., Ltd., Corofine Blue 02A) were placed in a pot mill.
) A primary blue aluminum pigment was prepared in the same manner as in Example 1, except that 4.8 g and 0.1 g of the pigment dispersant were used, and a secondary blue aluminum pigment was further prepared in the same manner as in Example 2.

A beer mug was experimentally produced by extrusion molding a mixture of 1 part by weight of this secondary blue aluminum pigment and 100 parts by weight of polycarbonate resin. The glittering blue powder was dispersed throughout the mug, resulting in a coat with a transparent and glittery feel.

Example 5 Mineral spirit 4 in a 1000ml Mitsuro flask
00 ml of aluminum pigment (IV (manufactured by Wa Aluminum Powder Co., Ltd., high brightness grade flaky aluminum paste 574PS, metal content 75.0
%, average particle size 13 μs), and 2.4 g of carboxylic acid having a double bond obtained by thermally polymerizing acrylic acid and soybean oil fatty acid (Diazid, manufactured by Harima Kasei Kogyo Co., Ltd.)
After stirring vigorously for 1 hour while maintaining the temperature at 55° C. while introducing N2 gas, the mixture was cooled to room temperature and filtered to obtain a thermally polymerized carboxylic acid-treated aluminum pigment. The diazide that meshed with this aluminum was 2.2
It was g.

In addition, 30 ml of mineral spirit and yellow pigment (manufactured by Ciba Geigy Co., Ltd., Cjnqua
s4a Pa5t Gold YT-915-D) I
Bg and 0.32 g of a pigment dispersant (manufactured by Kao Corporation, Homogenol L-100) were added, and the mixture was rotated at 30 rpm for 16 hours to disperse and pulverize the yellow pigment.

Next, the aluminum pigment adsorbed with Diazid and the dispersed and crushed yellow pigment were placed in 500 ml 11 Mitsuro flasks along with 80 ml of mineral spirit, and stirred vigorously for 10 minutes at room temperature while introducing N2 to adsorb the yellow pigment onto the surface of Diazid. I let it happen. Excess mineral spirit was removed by furnace to obtain a primary golden aluminum pigment.

Next, this primary golden aluminum pigment, Netloog
was placed in a Mitsuro flask containing 18 [10 ml of mineral spirit] without removing the mineral spirit, and 3.0 g of acrylic acid was added thereto, followed by stirring at a temperature of 60° C. for 15 minutes. Next, 30 g of trimethylolpropane trimethacrylate and 4.2 g of azobisisobutyronitrile were each added to 170 ml of mineral spirit.
, and added the solution dissolved in 150 ml of water over 3 hours.
The temperature was raised to 00°C to polymerize, and the surface of the second golden aluminum pigment was coated with a resin.

This was filtered to remove excess mineral spirits to create a secondary golden aluminum pigment.

15 parts by weight of this secondary golden aluminum pigment and 100 parts by weight of high-density polyethylene (HDPE) beads were mixed,
Upon blow molding, a transparent, golden-colored high-density polyethylene (HDPE) film was obtained.

Example 6 Mineral spirit 4 in a 1000ml Mitsuro flask
00 ml, and 140 g of aluminum pigment (manufactured by Showa Aluminum Powder Co., Ltd., high brightness grade flaky aluminum paste 725N, metal content 85.5%, average particle size 22 um), acrylic acid and soybean oil fatty acid. Add 2.4 g of thermally polymerized carboxylic acid having a double bond (manufactured by Harima Kasei Kogyo Co., Ltd., Diazid), maintain the temperature at 55°C while introducing N2 gas, stir vigorously for 1 hour, and then warm to room temperature. The mixture was cooled and filtered to obtain a thermally polymerized carboxylic acid-treated aluminum pigment. The amount of diazid adsorbed on this aluminum was 2.2 g.

In addition, 30ml of mineral spirit was added to a pot mill containing chromium steel balls with a diameter of 6+n+o in a 250ml glass bottle.
and red pigment (manufactured by Dainippon Ink and Chemicals Co., Ltd., C
o1ofine Red 236A) 24g and pigment dispersant (manufactured by Kao Corporation, homogenol L-100)
0.48 g was added and rotated at 30 rl III for 16 hours to disperse and pulverize the red pigment.

Next, the aluminum pigment adsorbing Diazid and the dispersed and pulverized red pigment were placed in a 500 ml Mitsuro flask along with 80 ml of mineral spirit.
The red pigment was adsorbed onto the surface of Diazid by stirring vigorously for 10 minutes at room temperature while introducing N2. Excess mineral spirit was removed from this to obtain a primary red aluminum pigment.

Next, 1150 g of this primary red aluminum pigment, Ne, was placed in a Mitsuro flask containing 1600 ml of mineral spirit without removing the mineral spirit, and 3.0 g of acrylic acid was added to the mixture at a temperature of 60°C for 150 g.
Stir for a minute. Then 30 g of trimethylolpropane trimethacrylate and 4 g of azobisisobutyronitrile
．． 2g each mineral spirit 170ml 1.15
Add the solution dissolved in 0ml and heat to 100℃ for 3 hours.
The temperature was raised to polymerize, and the surface of the red aluminum pigment was coated with a resin. This was filtered to remove excess mineral spirit to create a secondary red aluminum pigment.

When 15 parts by weight of this secondary red aluminum pigment and 100 parts by weight of polyethylene terephthalate were mixed and a container was formed by extrusion molding, a glittering red container was obtained.

〔Effect of the invention〕

The glittering plastic of the present invention can be used in all fields that require an unprecedentedly beautiful coloring effect with metallic color. For example, there are various plastic films made by blow molding, cabinets for various home appliances, tableware such as trays and cups made by injection molding or compression molding, and bodies and parts for automobiles made by extrusion molding.

Claims (2)

[Claims] (1) A coloring pigment is chemically adsorbed onto the surface of a metallic pigment via a carboxylic acid having at least one double bond and two carboxyl groups, which is obtained by thermally polymerizing one or more carboxylic acids having a double bond. The primary colored metallic pigment made of
．． A glittering plastic containing 1 to 50 parts by weight, and further containing other colorants and other additives if necessary. (2) A secondary colored metallic product obtained by coating the primary colored metallic pigment described in claim (1) with a polymer consisting of a radically polymerizable unsaturated carboxylic acid and a monomer having three or more radically polymerizable double bonds. 0.1 pigment as non-volatile content in 100 parts by weight of plastic
A glittering plastic containing up to 60 parts by weight, and further containing other colorants and other additives if necessary.